Front Nutr. 2026 Aug 11;13:1878741. doi: 10.3389/fnut.2026.1878741. eCollection 2026.
ABSTRACT
BACKGROUND: Preserved ratio impaired spirometry (PRISm) is a clinically relevant lung-function phenotype associated with adverse respiratory and systemic outcomes. Oxidative imbalance and metabolic dysfunction may contribute to impaired pulmonary reserve, but evidence from Chinese health examination populations remains limited. We examined the associations of oxidative balance score (OBS) and metabolic dysfunction indices with PRISm in Chinese adults.
METHODS: This hospital-based cross-sectional study included 1,311 adults undergoing routine health examinations between June 2024 and December 2025. PRISm was defined as FEV1/FVC ≥ 0.70 and FEV1 < 80% predicted. The standardized weighted OBS was constructed from dietary and lifestyle antioxidant/pro-oxidant components, and TyG, LAP, and AIP were analyzed as standardized continuous variables and quartiles. Multivariable logistic regression, restricted cubic splines, exploratory mediation analysis, and five-fold cross-validated machine-learning models were applied.
RESULTS: PRISm was identified in 92 participants (7.02%). The cohort mean (SD) values were 22.69 (4.98) for OBS, 8.69 (0.40) for TyG, 33.01 (16.73) for LAP, and 0.05 (0.36) for AIP. In fully adjusted models, higher OBS was associated with lower odds of PRISm (OR per 1-SD increase, 0.61; 95% CI, 0.48-0.77), whereas TyG, LAP, and AIP were positively associated with PRISm, with ORs of 1.52, 1.23, and 1.36, respectively. Restricted cubic splines showed an approximately linear inverse OBS-PRISm association. Higher OBS was also associated with more favorable metabolic profiles. Exploratory pathway analyses showed directionally consistent but statistically non-definitive indirect-effect estimates through metabolic indices. Machine-learning analyses showed modest discrimination and ranked TyG, OBS, LAP, and AIP among the leading predictors.
CONCLUSION: Favorable oxidative balance was independently associated with lower PRISm probability, whereas metabolic dysfunction indices were associated with higher PRISm probability. These findings support an oxidative-metabolic profile associated with early lung-function impairment, while longitudinal studies are needed to clarify temporality and causality.
PMID:42643239 | PMC:PMC13503214 | DOI:10.3389/fnut.2026.1878741
